> How do you seal the threads on the plugs > where > your xchanger zincs are mounted? The zincs should be mounted in a plug and the plug should have tapered threads on it. Tapered threads, if in good shape are self-sealing, if they are tightened adequately. The danger of using anything to seal these threads is the probability of electrically isolating the zinc from the housing, so a sealant is generally contraindicated. By the way, for anyone who may benefit from this thought, the threads on the zinc are standard straight threads. The zinc, or its broken off butt can be screwed out of the plug and a new zinc screwed in, which is much cheaper than buying a new zinc and plug combination. If the threads on the zinc do not screw in fully or easily, the threads can be chased by a standard straight tap and die of the correct size. If the broken off butt cannot be screwed out, it can be drilled out and the threads in the plug chased with the appropriate sized tap. When inserting a new zinc into a plug, electrical continuity must be maintained here also, so no sealant is used here either. Rudy Briney Bug, Panama City, Fl